POLYMER COMPOSITION FOR WATER ISOLATION Russian patent published in 2024 - IPC C09K8/508 

FIELD: oil industry.

SUBSTANCE: invention is related to regulation of the filtration properties of oil reservoirs, in particular to compositions for in-situ water isolation, as well as for levelling injectivity profiles of injection wells and limiting water inflow into production wells, eliminating annular and inter-layer flows. The polymer composition for waterproofing works contains, wt.%: fully saponified polyvinyl alcohol “16/1” – 0.7-8.5; organic liquid - dimethyl sulphoxide – 5.1-83.13; 10 wt.% aqueous solution of sodium hydroxide – 2-8; water – balance. Moreover, polyvinyl alcohol “16/1” is first dissolved in dimethyl sulphoxide, water is dosed into the resulting solution, and then 10 wt.% aqueous solution of sodium hydroxide is introduced.

EFFECT: improvement in the penetrating and waterproofing ability of the polymer composition, an increase in the coverage of the terrigenous formation by artificial flooding due to the inclusion in the development of low-permeability oil-saturated zones that were previously not covered by drainage.

1 cl, 2 tbl, 15 ex